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INVENTORIES, NET - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024
Inventory Disclosure [Abstract] |  |
Inventories at lower of LIFO cost or market | 81.00% | 81.00%
FIFO inventory, (lower) higher than reported | $ 8,995 | $ (14,425)
Effect of LIFO inventory liquidation on operating income | 2,757 | 370
Excess and obsolete inventory reserve | $ 23,192 | $ 29,176

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- Definition The effect of liquidating LIFO (last in first out) inventory layers on income. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 330 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SAB Topic 11.F) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480581/330-10-S99-3 + Details
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- Definition Amount of valuation reserve for inventory. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 330 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.BB) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480581/330-10-S99-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(6)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
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